1. Field of the Invention
The present invention relates to a mobile terminal device having a programmed-recording function. In particular, the present invention relates to a mobile terminal device that controls a programmed-recording function while recognizing a reception state.
2. Description of the Related Art
Today, mobile terminal devices, such as cellular phones, that have a television viewing/listening function based on a digital terrestrial broadcasting are available. Some of the mobile terminal devices have a function for recording video received via a digital terrestrial broadcasting, a function for recording video and audio data in internal memories of the mobile terminal devices or external memories during viewing/listening of the television, and a programmed-recording function for allowing a user to set programmed-recording information such as recording start time and automatically starting a recording function by using a timer.
Since the mobile terminal devices having the television viewing/listening function and the programmed-recording function are becoming smaller in size and lighter in weight and are used while on the go and while on the move, there are problems as follows.
As a first problem, the mobile terminal devices having the television viewing/listening function need to accomplish stable playback processing and recording processing of video data and audio data, based on the fact that the reception state of broadcast radio waves received from a broadcast station varies due to the movement.
As a second problem, a cellular phone, which is one example of the mobile terminal devices, requires a large power capacity in order to ensure long-term operation of the television viewing/listening function and the recording function in addition to a conventional verbal-communication function and a web-communication function. However, the mobile terminal device having a large power capacity leads to an increase in the manufacturing cost and an increase in the size of the mobile terminal device. Thus, it is necessary to reduce the power consumed for the television viewing/listening function and the recording function in order to ensure long-term operation of the mobile terminal device.
As a third problem, the mobile terminal device requires a memory capacity that ensures long-term recording, when the recording function of the mobile terminal device is used to record a broadcast program. Thus, the mobile terminal device may be provided with a large-capacity internal memory or external memory, but such a configuration leads to an increase in the manufacturing cost and an increase in the size of the mobile terminal device; It is necessary to prevent unwanted consumption of the memory in order to ensure long-term recording of a broadcast program and so on.
In order to overcome the above-described problems, Japanese Unexamined Patent Application Publication No. 2007-74582 (Patent Document 1) discloses a mobile terminal device that prevents battery or memory consumption due to unwanted recording of video data and audio data having low reception qualities. In Patent Document 1, before the recording using the programmed-recording function is started, the mobile terminal device measures reception quality of a broadcast program and notifies a user whether or not the broadcast program can be stably recorded.
Japanese Unexamined Patent Application Publication No. 2006-86667 (Patent Document 2) discloses a mobile wireless terminal that eliminates memory and power consumption due to unwanted recording processing. In Patent Document 2, when the programmed-recording function is used to perform video and audio recording processing and the reception quality that is determined from electric field strength decreases, the recording processing is stopped and a notification indicating so is notified a user.
In Patent Document 1, when the mobile terminal device measures the reception quality for a broadcast program to be subjected to the recording processing and the reception quality decreases, the mobile terminal device notifies only that the reception quality decrease. Thus, even if the reception quality improves after notifying the user, the mobile terminal device cannot perform recording processing of a broadcast program on which the user desires to perform the recording processing. In addition, Patent Document 1 does not give any consideration to the amount of power consumption involved in the measurement of the reception quality.
Patent Document 2 does not give any consideration to the reception quality of broadcast radio waves before programmed-recording start time. Also, during execution of the recording processing, even when the user requires an appropriate recording quality for each broadcast program on which he or she desires to perform recording processing, the user's intension cannot be sufficiently reflected.